[BigQuery Omni](https://cloud.google.com/bigquery/docs/omni-introduction) only allows querying data stored in an external system, due to its [limitation](https://cloud.google.com/bigquery/docs/omni-introduction#limitations), it can not create external tables in BigQuery. Yes, scripting would do but natively it is not yet possible.

Thanks! This is interesting to be available natively. On Google's side, there is a feature request that you can file but there is no timeline on when it can be done, you can request this feature so more community members can benefit when this is done by Google.